A quick glance across the map of Europe, including the mess of Brexit and Ireland's woes can be traced by to the ideas of  "taking back control of our borders.”

With the Brexit withdrawal agreement signed by the EU leaders in Brussels last weekend, the focus of attention now shifts to the British Parliament to see if Prime Minister Theresa May can get it accepted when a vote is taken there in a couple of weeks.  

Both May and the EU leaders are insisting that it's this deal or no deal.  But opposition is so strong in Westminster she is facing an uphill battle.  

If she fails and Britain crashes out of the EU next March without a deal, the consequences for Ireland will be enormous.  The coming weeks will tell that story and we just have to await the outcome.

But for now, it's worth remembering that one issue more than any other was the cause of the disastrous decision taken by the British people in 2016 to leave the EU.  That issue, characterized as "taking back control of our borders,” was immigration.   

And it's not just Britain. Immigration has caused a major political shift in countries across Europe as voters have lost patience with existing liberal policies and turned to parties that have promised a tougher line.

The result is that there are now populist or right-wing parties in government in Italy, Hungary, Austria and Poland, and they are wielding significant influence in other countries in Eastern Europe like Slovenia, Slovakia and the Czech Republic. 

Even in the big, traditionally liberal countries in Western Europe, the shift is palpable.  Most of the potential successors to German Chancellor Angela Merkel in are expressing disapproval of her liberal immigration decisions in the recent past.  In France, President Emmanuel Macron is in deep trouble, and the anti-immigrant Marine Le Pen and her national front style party could yet stage a comeback. 

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In the Netherlands, the growth of the populist Freedom Party is already concerning.  In Denmark, Finland and even in ultra-liberal Sweden, hardline parties are on around 20 percent of the vote.  

In the last election in Switzerland, of all places, the populist Swiss People's Party won 29 percent support.  The trend across Europe is undeniable. 

Of course, immigration is not the only issue driving this, but it is a common factor everywhere.  And the reaction of the political establishment in most European countries has not helped.  

Instead of listening to the concern, the reaction has been to belittle the populist parties and those who support them as racist, xenophobic, fascist, etc. Most of this reaction comes from the comfortable, liberal layers of society who have private health insurance, send their kids to private schools and are insulated from the pressure that immigration puts on public hospitals, schools, services, and housing.  

The practical effect of increased immigration is most keenly felt in working class and deprived areas where the struggle for an acceptable standard of living seems to be getting harder all the time.  

Added to this is a basic uneasiness in many European countries about the arrival of foreign lifestyles and different values, as well as a dilution of local culture, concerns which are not allayed by the official promotion of the attractions of multi-culturalism.  

It's not racist to want to preserve your own way of life and values and increasingly in Europe people are no longer afraid to say so. That is evident in the numbers now voting for the so-called populist parties.  

This is a growing problem for the long-established, centrist, largely liberal parties across Europe. They have been asleep at the wheel, ignoring or dismissing the growing concerns among their voters about immigration and the financial and social costs involved.

The danger is that this disregard could result in them being replaced by parties that are not just populist but extremely right wing.  This was a threat alluded to last week from an unexpected source, Hillary Clinton.  

In an interview with The Guardian newspaper in Britain, Clinton said that Europe must get a handle on immigration to combat the growing threat from right-wing populists.  She called on Europe's leaders to send out a stronger signal that they are “not going to be able to continue to provide refuge and support” (to an unlimited number of immigrants in the future).  

Clinton, of course, knows all about this thanks to her defeat by "Build the Wall" Trump.  What she said came across as a rueful recognition of reality, a lesson she has learned the hard way and too late, and one she believes European politicians should be taking on board.  

But instead of that, the liberal establishment across Europe had a minor meltdown over her comments, suggesting she was enabling the xenophobes.  The truth is that what she said was merely a statement of fact.  

No more than the U.S. can cope with unlimited migration from South America, Europe cannot absorb unlimited migration from Africa and Asia.  A refusal to accept that basic reality will lead to increasing dissatisfaction among voters in Europe and growing support for populist and far-right parties that promise a much tougher line.  

Acceptance of that reality means an acceptance that migration has to be controlled and regulated.  It means that rules for legal immigration have to be enforced and that the many ways the rules are side-stepped have to be shut down.

This can be hard for liberals to accept since their first instinct is to find a way around the law to help migrants who are trying to get in or are already in illegally.  They focus on the individual human stories involved instead of on the immigration laws and rules.     

That is understandable.  It's always easier to be a do-gooder than to take hard decisions and enforce them.  And the longer tough decisions are avoided, the more difficult and complex action becomes, as two recent cases in Ireland have shown.

The first of these concerned Nonso Muojeke, a 12-year-old Nigerian schoolboy in Tullamore in Co. Offaly, who was threatened with deportation along with his mother and older brother. His schoolmates and the local community demonstrated in his support, and thousands signed a petition pleading that the family be allowed to stay.    

The family had arrived in Ireland in 2007 when Nonso was two.  Their application for asylum was declined in 2009, but continued appeals and court moves enabled them to stay on until a deportation order was finally issued last June.  Now, following all the publicity, they will be allowed to stay.  

The other case involved a nine-year-old boy called Eric Zhi Ying Xue who was born in Ireland to a Chinese mother who arrived here 12 years ago and remained illegally.  She made continued attempts to gain residence but failed and a deportation order was served against her in 2015.

Her latest appeal was rejected earlier this year which meant she and her son were to be deported to China, despite the fact that the boy had never been there and did not speak the language.  

Tens of thousands of people in Bray, Co. Wicklow, where they live, signed a petition to allow them to stay, and one government minister who lives in the area has now indicated that this is likely to be successful.  That is great news for the boy, but it also raises a number of questions, some of which go back 20 years.  

Back then Ireland became the only country in the EU which automatically granted citizenship rights at birth, which meant that any child born on the island of Ireland was entitled to Irish citizenship.  This right was introduced as part of the Good Friday Agreement in 1998.   

The original intention was that people born in Northern Ireland would be entitled to citizenship in the South.  But the move opened a very wide loophole.  

Women from Africa, Asia and elsewhere realized that if they could get to Ireland and have a baby here, the child would be an Irish citizen and therefore entitled to live here or anywhere else in the EU.  And that meant the mother would be allowed to stay as well. 

The result was an influx over the following years of foreign women arriving here, often with their partners, to claim asylum knowing that if they gave birth here before a final decision was reached they would be able to stay.  In 1999, only two percent of babies born in the Republic of Ireland had non-national parents but by 2003 the figure was almost 20 percent.  

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Dublin's main maternity hospitals were under pressure with so many non-EU women arriving, often in the final stage of pregnancy.  So the government had to act and the following year, 2004, the Irish voted by almost 80 percent to end automatic citizenship rights. 

Because of this, the Chinese Irish boy in Bray did not have the right to stay, even though he was born here.  But enforcing this is difficult as we have seen not only from this case but others as well.

The main problem is the ludicrous amount of time it takes to reach a conclusion in asylum cases here.   The process has become a mini-industry for the legal profession, with endless appeals and court appearances, all funded by the taxpayer.  By the time the process is exhausted the family has put down roots, with kids in school, etc.   

In response to these two cases, Labour Party senators have proposed new legislation that will restore the automatic right to citizenship for any child here after three years.  That sounds humane and responsible and it plays into the well of emotion that has surrounded these cases.

But anyone who thinks such a change would not have consequences for migration numbers is naive.  It could be done if there was an absolute time limit on appeals in asylum/residency cases of a year or two but there is no sign of that happening.  

As we said, immigration is still a highly emotive topic here, an issue that is not going away.